我收到 ClassCastException 错误。我不知道为什么。试图清理我的项目，但什么也没发生。提前致谢！
日志猫：
04-30 18:03:44.122: W/dalvikvm(276): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
04-30 18:03:44.142: E/AndroidRuntime(276): FATAL EXCEPTION: main
04-30 18:03:44.142: E/AndroidRuntime(276): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.letsplay.gamster/com.letsplay.gamster.TutorialOne}: java.lang.ClassCastException: android.widget.TextView
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.os.Handler.dispatchMessage(Handler.java:99)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.os.Looper.loop(Looper.java:123)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread.main(ActivityThread.java:4627)
04-30 18:03:44.142: E/AndroidRuntime(276): at java.lang.reflect.Method.invokeNative(Native Method)
04-30 18:03:44.142: E/AndroidRuntime(276): at java.lang.reflect.Method.invoke(Method.java:521)
04-30 18:03:44.142: E/AndroidRuntime(276): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
04-30 18:03:44.142: E/AndroidRuntime(276): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
04-30 18:03:44.142: E/AndroidRuntime(276): at dalvik.system.NativeStart.main(Native Method)
04-30 18:03:44.142: E/AndroidRuntime(276): Caused by: java.lang.ClassCastException: android.widget.TextView
04-30 18:03:44.142: E/AndroidRuntime(276): at com.letsplay.gamster.TutorialOne.onCreate(TutorialOne.java:28)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-30 18:03:44.142: E/AndroidRuntime(276): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
04-30 18:03:44.142: E/AndroidRuntime(276): ... 11 more
04-30 18:03:44.172: W/ActivityManager(59): Force finishing activity com.letsplay.gamster/.TutorialOne
04-30 18:03:44.182: W/ActivityManager(59): Force finishing activity com.letsplay.gamster/.menu
04-30 18:03:44.651: I/ARMAssembler(59): generated scanline__00000077:03515104_00000000_00000000 [ 33 ipp] (47 ins) at [0x315a58:0x315b14] in 398622 ns
04-30 18:03:44.681: W/ActivityManager(59): Activity pause timeout for HistoryRecord{45071338 com.letsplay.gamster/.TutorialOne}
04-30 18:03:45.791: I/Process(276): Sending signal. PID: 276 SIG: 9
04-30 18:03:45.811: I/ActivityManager(59): Process com.letsplay.gamster (pid 276) has died.
///////////////////////////////////////// ///////////////////////////// java:
package com.letsplay.gamster;
import android.app.Activity;
import android.graphics.Typeface;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.TextView;
public class TutorialOne extends Activity implements OnCheckedChangeListener {
TextView textOut;
EditText textIn;
RadioGroup radioG, styleG;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.tutorial1);
textOut = (TextView) findViewById(R.id.textChanges);
textIn = (EditText) findViewById(R.id.editText1);
radioG = (RadioGroup) findViewById(R.id.textGravity);
radioG.setOnCheckedChangeListener(this);
styleG = (RadioGroup) findViewById(R.id.textStyle);
styleG.setOnCheckedChangeListener(this);
Button ok1 = (Button) findViewById(R.id.buttonOK);
ok1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
textOut.setText(textIn.getText());
}
});
}
public void onCheckedChanged(RadioGroup group, int checkedId) {
// TODO Auto-generated method stub
switch(checkedId){
case R.id.radioLeft:
textOut.setGravity(Gravity.LEFT);
break;
case R.id.radioCenter:
textOut.setGravity(Gravity.CENTER);
break;
case R.id.radioRight:
textOut.setGravity(Gravity.RIGHT);
break;
case R.id.radioNormal:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.NORMAL), Typeface.NORMAL);
break;
case R.id.radioBold:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD), Typeface.BOLD);
break;
case R.id.radioItalic:
textOut.setTypeface(Typeface.defaultFromStyle(Typeface.ITALIC), Typeface.ITALIC);
break;
}
}
}
///////////////////////////////////////// //////////////// xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:orientation="vertical">
<EditText android:text="" android:id="@+id/editText1"
android:layout_width="fill_parent" android:layout_height="wrap_content" />
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:orientation="horizontal" android:weightSum="2">
<TextView android:id="@+id/textStyle" android:layout_width="fill_parent"
android:layout_height="wrap_content" android:layout_weight="1"
android:gravity="center" android:text="Style" android:textStyle="bold" />
<TextView android:id="@+id/textGravity" android:layout_width="fill_parent"
android:layout_height="wrap_content" android:layout_weight="1"
android:gravity="center" android:text="Gravity" android:textStyle="bold" />
</LinearLayout>
<LinearLayout android:layout_width="fill_parent"
android:layout_height="wrap_content" android:orientation="horizontal"
android:weightSum="2">
<RadioGroup android:id="@+id/radioStyle"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_weight="1" android:orientation="vertical">
<RadioButton android:id="@+id/radioNormal"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Normal" />
<RadioButton android:id="@+id/radioItalic"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Italic" />
<RadioButton android:id="@+id/radioBold"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Bold" />
</RadioGroup>
<RadioGroup android:id="@+id/radioGravity"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_weight="1" android:orientation="vertical">
<RadioButton android:id="@+id/radioLeft"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Left" />
<RadioButton android:id="@+id/radioCenter"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Center" />
<RadioButton android:id="@+id/radioRight"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:text="Right" />
</RadioGroup>
</LinearLayout>
<TextView android:id="@+id/textChanges" android:layout_width="fill_parent"
android:layout_height="wrap_content" android:gravity="center_horizontal"
android:text="Введите текст" />
<Button android:id="@+id/buttonOK" android:layout_width="fill_parent"
android:layout_height="wrap_content" android:text="OK" />
</LinearLayout>